Malocclusion - difference between overbite, overjet and open bite

June 02, 2017

Ideally your teeth should all fit in your mouth easily, without crowding or spacing problems. But unfortunately most people are not born with perfect teeth. Generally alignment problems (malocclusions) are hereditary. They can also stem from bad habits, lifestyle choices, and trauma. This improper alignment of teeth can lead to serious oral health complications, especially if teeth cannot perform vital functions because of misalignment.

How bad is my malocclusion?

Malocclusion can impact your speech, eating habits, breathing, and even alter the appearance of your face. It can cause jaw pain, enamel wear, soft tissue damage, and increase your risk of dental disease and cavities. Through routine dental exams and x-rays the dentist can detect malocclusion and classify it based on severity and type. Main types of malocclusion include overbite, overjet and open bite. Many patients get them wrong, and while similar, these three conditions are different.

What is Overbite?

This is a vertical measurement of the overlap between the top teeth and the bottom teeth located at the front of the mouth. The condition often occurs when upper teeth are slightly longer than normal, or more erupted. It can be measured in millimeters or percentage, but most often the dental professionals refer to it as reduced, normal, or increased overbite. Most people have an overbite of some degree, and it isn’t necessarily a bad thing. Problems arise if an overbite is too large, and upper incisors cover more than a third of the lower teeth. The lower teeth bite too deeply behind the top teeth. This causes abnormal and unhealthy wear against the upper teeth. In the most extreme cases (increased overbite) the lower teeth can even reach the gums, causing more damage.

Treatment for Overbite

Overbite can stem from the underdevelopment of the lower jaw, or a discrepancy in the size of front teeth. In some cases an orthodontist can use orthodontic therapy to bring the jaws into proper alignment. This treatment works best in younger patients, whose skeletal structure is more malleable. A severe overbite in adults caused by a skeletal problem is more difficult. It cannot be corrected with braces alone. These cases often require surgery to reposition the jaw before braces, and perhaps even contouring or resizing the teeth afterward to bring teeth into a normal position.

What is Overjet?

This occurs where there is a large discrepancy in the horizontal distance between the upper and lower front teeth. Typically upper teeth protrude visibly, commonly called buck teeth. Teeth may even be straight, but just splayed outward in front of lower teeth. This prevents the teeth and lips from coming together when the mouth is closed. As a result patients often suffer from chapped lips and dry mouth. People with overjet are also at a greater risk for accidental trauma, because teeth stick outward.

Orthodontic treatment not only improves esthetics, but also reduces the risk of other injuries and conditions. And it is best to seek treatment early, reducing the duration and extent of treatment. To know if you have malocclusion severe enough for orthodontic treatment, visit your dentist or orthodontist for an evaluation.

What is open bite?

If the patient has the back teeth in contact and the front teeth are not meeting properly, the condition is called open bite. It is a type of malocclusion, usually caused by bad habits. Open bite can be due to thumb sucking, sucking pencils/pens or tongue thrusting (also known as infantile swallow). The outlook of the patient is significantly affected and the teeth have the appearance that they are ‘sticking out’. People with open bite struggle to bite off with their front teeth and the mastication process is longer and inefficient. In a long run, the open bite can causes overloading of the back teeth and problems with fractured teeth and chipped off fillings. Open bite is measured in millimeters – the space between the incisal edges of the anterior teeth.

Treatment for open bite

Depending on the age of the patient open bite can be treated in several ways. Eliminating the etiological factor is the main part of the treatment. Without breaking the bad habit, the misalignment may come back and this will be considered as an orthodontic relapse. Fixing overbite is easier if the patient is 8-13 years old. This is the age when jaws are growing and navigating the teeth eruption and jaws development is quite easy. Treatment doesn’t last that long (6 months – 2 years depending on the severity of the condition) and retainers can be removed a few years after the finish of the orthodontic treatment. Open bite in children can be fixed with a Williams appliance, Bionator or conventional brackets depending on the case. Treating open bite in adults is a more complicated job – the course of treatment may last up to 3 years and the retainers must be worn for life. Orthodontic brackets and exercises for breaking the bad habits are recommended for treating open bite in adults.